The present invention relates to firearms, in general and, in particular, to a safety mechanism for preventing inadvertent firing of a firearm, particularly a handgun.
Firearms of various designs have long been known. One type of firearm has a mechanically activating primer. The energy needed to activate the primer is relatively low. Thus, these firearms suffer from a major disadvantage in that, if the firearm is dropped on the muzzle, the firing pin can move forward with sufficient energy to actuate the primer.
There is shown in U.S. Pat. No. 4,208,947 a safety mechanism for a firearm including a hammer block engageable with the hammer to prevent the hammer from moving into engagement with the firing pin. The hammer block is manually shifted between its active and inactive positions through a safety cam having a positive driving connection with the block. As the cam is moved to shift the block from its non-blocking to its blocking position, the cam also engages the sear to release the sear from the trigger and to allow the hammer to move from its cocked position into a safety position in engagement with the hammer block. This safety mechanism is relatively complicated to manufacture and maintain.
There is known, from U.S. Pat. No. 6,145,234 to Fluhr, a firing pin safety catch mechanism including a one-piece leaf spring extending the length of the breechblock of the firearm, the spring comprising a spring arm, a safety catch and a beveled release part. The safety catch has a first position, wherein the safety catch engages a catch surface of a firing pin, to secure the firing pin in a rest position, and a second position, wherein the safety catch disengages the catch surface, to release the firing pin for movement out of the rest position. The release part acts as a camming surface acting together with the hammer to release the spring.
Another firing pin safety catch mechanism is shown in U.S. Pat. No. 4,658,529 to Bertolini. This mechanism includes an inertial firing pin with an annular groove. The safety is provided with a rib canted toward the hammer side of the firing pin. When the safety is moved to an xe2x80x9conxe2x80x9d position, the rib enters the firing pin groove and cams the firing pin so as to retract and lock the pin in a sheathed position within the piston slide.
Yet another firing pin safety device is shown in U.S. Pat. No. 4,090,316 to Volkmar. This patent discloses a firing pin which is pivotable between safety and firing positions, and a hammer which has a striking surface engaging the firing pin when the firing pin is in its firing position, and recess which receives the firing pin when in its safety position.
All of these patents discloses safety devices wherein the firing pin lock is releases directly by the hammer, i.e., the lock and release are a single element.
Accordingly, there is a long felt need for a safety mechanism for a firearm which will prevent inadvertent firing if the handgun receives a shock, by preventing the hammer from inadvertently activating the firing pin, and which is simple to manufacture and actuate, and which includes a safety mechanism to prevent inadvertent release of the firing pin lock.
The present invention provides a safety mechanism for a handgun having a pivotal hammer arranged to activate a firing pin, the mechanism including a locking element for engaging the firing pin and preventing its movement, and a separate release element for releasing the locking element, the release element being releasable upon being hit by the hammer with a force above a pre-determined threshold.
According to one embodiment of the invention, the locking element includes a firing pin plate through which one end of the firing pin passes, a blocking spring in the firing pin plate, a notch in the firing pin, the blocking spring engaging the notch in a locked orientation, and the blocking spring being out of engagement with the notch in a firing orientation, and a release element for causing the blocking spring to move from the locked orientation to the firing orientation.
According to a preferred embodiment, the blocking spring is mounted in a groove cut in the firing pin plate, and held in the locked orientation by a plunger, the plunger being located so as to be hit by the hammer before the hammer hits the end of the firing pin.
Preferably, the plunger has a conical cross section, the blocking spring being located so as to slide along the plunger when moving from the locked to the unlocked orientation.
Most preferably, the hammer is arranged to hit both the plunger and the firing pin, the hitting of the plunger causing release of the blocking spring so that the firing pin is in the firing orientation.
There is also provided, in accordance with the present invention, a method for preventing inadvertent firing of a firearm having a firing pin seated in a firing pin block and a hammer for actuating the firing pin, the method including mounting a locking element in the firing pin block, mounting a separate release element, coupled to the locking element, in the firing pin block, and releasably engaging the firing pin by the locking element, the locking element being released upon being hit by the hammer with a force above a pre-determined threshold.